Video: Scoop: Leno's last primetime show

LOS ANGELES — The Jay Leno/Oprah Winfrey/David Letterman promo for the “Late Show” was hailed as one of the more memorable spots from Super Bowl Sunday.

And as far as Leno is concerned, he was just happy to be a part of it.

“It was great fun,” Leno told “The Jay Leno Show” audience on Monday night. “I want to thank Dave for making me a part of his promo. I was glad to promote his show. Dave, thank you very much. I appreciate it.”

As previously reported on AccessHollywood.com, the commercial was Letterman’s idea. And once it was presented to Leno, he jumped at the chance to do it.

“I thought it was great. Because no matter what animosity there is among comedians — a good joke is a good joke,” Leno said.

So what happened when the two former-and-soon-to-be-again late night competitors saw each other at the Ed Sullivan Theater in New York, where the spot was taped? According to Leno, all their past problems vanished.

Slideshow: Jay Leno, 'Tonight' and beyond
“I walk in and I see Dave. He puts his hand out and we shake hands. And you know, whatever happened the last 18 years disappeared,” Leno continued. “It was great to see my old friend again. It was wonderful… We talked about the old days. We told some jokes. It was really good to see him.”

However, the top secret project, which was kept under wraps from both Letterman and Leno’s employees, caught the eye of one NBC executive when Leno returned from his undercover excursion.

“The next day [after I returned], an NBC executive comes to me and says, ‘Jay, we have a problem. Last night, I got word David Letterman shot some kind of secret show. We know a black SUV pulled up. There was security and a hooded figure came in the side of the building,’” Leno recounted to his audience.

“Who do you think it was?” Leno asked the exec, keeping the charade going.

“We think it was President Obama,” the exec told Leno, drawing a laugh from the host and the crowd as he shared the story.

“OK, keep me posted!” Leno continued to play along.

But now that the secret is out, do Leno and Letterman have any further plans to collaborate in the future?

“The commercial went so well, Dave and I have decided to go to Vancouver and compete in the two-man luge,” Leno joked.

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